src/main/c/seasocks/Connection.h

// Copyright (c) 2013, Matt Godbolt
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without 
// modification, are permitted provided that the following conditions are met:
// 
// Redistributions of source code must retain the above copyright notice, this 
// list of conditions and the following disclaimer.
// 
// Redistributions in binary form must reproduce the above copyright notice, 
// this list of conditions and the following disclaimer in the documentation 
// and/or other materials provided with the distribution.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
// POSSIBILITY OF SUCH DAMAGE.

#pragma once

#include "seasocks/ResponseCode.h"
#include "seasocks/WebSocket.h"

#include <netinet/in.h>

#include <sys/socket.h>

#include <inttypes.h>
#include <list>
#include <memory>
#include <string>
#include <vector>

namespace seasocks {

class Logger;
class ServerImpl;
class PageRequest;
class Response;

class Connection : public WebSocket {
public:
    Connection(
            std::shared_ptr<Logger> logger,
            ServerImpl& server,
            int fd,
            const sockaddr_in& address);
    virtual ~Connection();

    bool write(const void* data, size_t size, bool flush);
    void handleDataReadyForRead();
    void handleDataReadyForWrite();

    int getFd() const { return _fd; }

    // From WebSocket.
    virtual void send(const char* webSocketResponse) override;
    virtual void send(const uint8_t* webSocketResponse, size_t length) override;
    virtual void close() override;

    // From Request.
    virtual std::shared_ptr<Credentials> credentials() const override;
    virtual const sockaddr_in& getRemoteAddress() const override { return _address; }
    virtual const std::string& getRequestUri() const override;
    virtual Request::Verb verb() const override { return Request::WebSocket; }
    virtual size_t contentLength() const override { return 0; }
    virtual const uint8_t* content() const override { return NULL; }
    virtual bool hasHeader(const std::string&) const override;
    virtual std::string getHeader(const std::string&) const override;

    void setLinger();

    size_t inputBufferSize() const { return _inBuf.size(); }
    size_t outputBufferSize() const { return _outBuf.size(); }

    size_t bytesReceived() const { return _bytesReceived; }
    size_t bytesSent() const { return _bytesSent; }

    // For testing:
    std::vector<uint8_t>& getInputBuffer() { return _inBuf; }
    void handleHixieWebSocket();
    void handleHybiWebSocket();
    void setHandler(std::shared_ptr<WebSocket::Handler> handler) {
        _webSocketHandler = handler;
    }
    void handleNewData();

private:
    void finalise();
    bool closed() const;

    void closeWhenEmpty();
    void closeInternal();

    void handleHeaders();
    void handleWebSocketKey3();
    void handleWebSocketTextMessage(const char* message);
    void handleWebSocketBinaryMessage(const std::vector<uint8_t>& message);
    void handleBufferingPostData();
    bool handlePageRequest();

    bool bufferLine(const char* line);
    bool bufferLine(const std::string& line);
    bool flush();

    bool handleHybiHandshake(int webSocketVersion, const std::string& webSocketKey);

    // Send an error document. Returns 'true' for convenience in handle*() routines.
    bool sendError(ResponseCode errorCode, const std::string& document);

    // Send individual errors. Again all return true for convenience.
    bool sendUnsupportedError(const std::string& reason);
    bool send404();
    bool sendBadRequest(const std::string& reason);
    bool sendISE(const std::string& error);

    void sendHybi(int opcode, const uint8_t* webSocketResponse, size_t messageLength);

    bool sendResponse(std::shared_ptr<Response> response);

    bool processHeaders(uint8_t* first, uint8_t* last);
    bool sendData(const std::string& type, const char* start, size_t size);

    struct Range {
        long start;
        long end;
        size_t length() const { return end - start + 1; }
    };

    bool parseRange(const std::string& rangeStr, Range& range) const;
    bool parseRanges(const std::string& range, std::list<Range>& ranges) const;
    bool sendStaticData();

    int safeSend(const void* data, size_t size);

    void bufferResponseAndCommonHeaders(ResponseCode code);

    std::list<Range> processRangesForStaticData(const std::list<Range>& ranges, long fileSize);

    std::shared_ptr<Logger> _logger;
    ServerImpl &_server;
    int _fd;
    bool _shutdown;
    bool _hadSendError;
    bool _closeOnEmpty;
    bool _registeredForWriteEvents;
    sockaddr_in _address;
    size_t _bytesSent;
    size_t _bytesReceived;
    std::vector<uint8_t> _inBuf;
    std::vector<uint8_t> _outBuf;
    std::shared_ptr<WebSocket::Handler> _webSocketHandler;
    bool _shutdownByUser;
    std::unique_ptr<PageRequest> _request;

    enum State {
        INVALID,
        READING_HEADERS,
        READING_WEBSOCKET_KEY3,
        HANDLING_HIXIE_WEBSOCKET,
        HANDLING_HYBI_WEBSOCKET,
        BUFFERING_POST_DATA,
    };
    State _state;

    Connection(Connection& other) = delete;
    Connection& operator =(Connection& other) = delete;
};

}  // namespace seasocks